Status of Emacs addons?

Hello all,

I am new to GNU Smalltalk, so please forgive my ignorance.

I'm running Emacs 25.2.1, and my naive attempt to load the
elisp files returns:
(void-variable @WITH_EMACS_COMINT_TRUE@)
And additional void variables occur (such as @bindir@)
throughout the files. Am I supposed to edit these
variables myself? (The gst info file makes me believe
the answer is yes).

Additionally, I've never come accross a *.el.in file before.
Google searching revealed nothing. Is there a standard
Emacs convention I am missing here?

Thank you for your time,

Andrew